1. Field of the Invention
The present invention relates to an attachment and detachment mechanism including a driving side coupling and a driven side coupling to be coupled to and separated from each other in an attachment and detachment of a driving side main body and a driven side main body.
2. Description of the Related Art
There has been conventionally used an attachment and detachment mechanism including a driving side coupling and a driven side coupling to be coupled to and separated from each other in an attachment and detachment of a driving side main body and a driven side main body.
Endoscopes including such attachment and detachment mechanisms are disclosed, for example, in Jpn. Pat. Appln. KOKAI Publication No. 2002-224016 and International Publication No. 2006/59721 pamphlet. Each of these endoscopes includes a motor unit and an insertion portion to be attached to or detached from each other. In the motor unit, a circular-plate-shaped driving side coupling is coaxially coupled to the terminal end portion of a driving side shaft portion. On the other hand, in the elongate insertion portion to be inserted into a body cavity, a circular-plate-shaped driven side coupling is coaxially coupled to the terminal end portion of a driven side shaft portion at the proximal end portion of the insertion portion, while a bending portion to be bent by the rotation of the driven side shaft portion is provided at the terminal end portion of the insertion portion.
In the attachment and detachment mechanism of Jpn. Pat. Appln. KOKAI Publication No. 2002-224016, an engaging concave portion extends in the radial direction of the driving side shaft portion in a terminal end face of the driving side coupling, an engaging convex portion extends in the radial direction of the driven side shaft portion in a terminal end face of the driven side coupling, and the engaging convex portion is to be slidably inserted into and removed from the engaging concave portion along the longitudinal direction of the engaging concave portion. The engaging convex portion is inserted into and removed from the engaging concave portion and so the driving side coupling and the driven side coupling are coupled to and separated from each other.
In the attachment and detachment mechanism in the International Publication No. 2006/59721 pamphlet, engaging concave portions and engaging convex portions are provided sequentially in a circumferential direction in terminal end faces of a driving side coupling and a driven side coupling. Further, a pin protrudes from the terminal end face of the certain engaging convex portion of the driven side coupling of the insertion portion, and a pin guide is provided in the motor unit. In the attachment of the motor unit and the insertion portion, when the driving side coupling and the driven side coupling are moved to face each other, the pin of the driven side coupling is guided by the pin guide of the motor unit and so the engaging concave portions and engaging convex portions of the driven side coupling are disposed opposite to the engaging convex portions and engaging concave portions of the driving side coupling, and then, when an engaging and separation button is operated, the driving side coupling is axially moved to the driven side coupling and so the driving side coupling and the driven side coupling are coupled to each other. On the other hand, in the removal of the motor unit and the insertion portion, the engaging and separation button is operated and so the driving side coupling is axially moved from the driven side coupling, and the driving side coupling and the driven side coupling are thus separated from each other.